Create/Manage VirtualBox VMs from the Command Line
Note to self, here’s a quick recipe for creating a Virtual Machine using the VirtualBox command line,

Create the VM,

VBoxManage createvm --name "io" --register
VBoxManage modifyvm "io" --memory 512 --acpi on --boot1 dvd
VBoxManage modifyvm "io" --nic1 bridged --bridgeadapter1 eth0
VBoxManage modifyvm "io" --macaddress1 XXXXXXXXXXXX
VBoxManage modifyvm "io" --ostype Debian
Attach storage, add an IDE controller with a CD/DVD drive attached, and the install ISO inserted into the drive,

VBoxManage createhd --filename ./io.vdi --size 10000
VBoxManage storagectl "io" --name "IDE Controller" --add ide

VBoxManage storageattach "io" --storagectl "IDE Controller"  \
    --port 0 --device 0 --type hdd --medium ./io.vdi

VBoxManage storageattach "io" --storagectl "IDE Controller" \
    --port 1 --device 0 --type dvddrive --medium debian-6.0.2.1-i386-CD-1.iso
Starting the VM for installation,

VBoxHeadless --startvm "io" &
This starts the VM and a remote desktop server. Redirect RDP port if necessary,

ssh -L 3389:127.0.0.1:3389 <host>
Shutting down the VM,

VBoxManage controlvm "io" poweroff
Remove install Media,

VBoxManage modifyvm "io" --dvd none
Alternatively install OS using the GUI, configure it then export is as an appliance upload to the server then import it using,

VBoxManage export "io" --output ioClone.ovf
VBoxManage import ioClone.ovf
Starting the VM,

VBoxHeadless --startvm "io" --vrde off &
This starts the VM without remote desktop support.

Delete the VM,

VBoxManage unregistervm io --delete
Mount Guest Additions

VBoxManage storageattach "io" --storagectl "IDE Controller" \
    --port 1 --device 0 --type hdd --medium /usr/share/virtualbox/VBoxGuestAdditions.iso
Install Guest Additions,

mkdir /mnt/dvd
mount -t iso9660 -o ro /dev/dvd /mnt/dvd
cd /mnt/dvd
./VBoxLinuxAdditions.run
Adding/removing shared folders,

vboxmanage sharedfolder add "io" --name share-name --hostpath /path/to/folder/ --automount
vboxmanage sharedfolder remove "io" --name share-name
To mount it on the guest,

sudo mount -t vboxsf -o uid=$UID share-name /path/to/folder/share/